The possibility of shortening the test length of beef bulls will be of great benefit. Not only will it save costs since collecting feed intake data is expensive, but more animals can be tested, enabling higher selection pressure on efficiency. Individual feed intake data from 3 070 Simmentaler bulls were consolidated into a standard 84-day test and four alternative test periods. The Pearson and Spearman correlations were estimated in respect of the conventional growth and efficiency traits (average daily gain, daily feed intake and feed conversion ratio) and alternative efficiency traits (metabolic mid weight, net daily gain and net feed intake) for the different test lengths. Shortening of the test length does not seem feasible, since the correlation for traits among different test lengths are too low. It is concluded that daily feed intake can be measured accurately at shorter test lengths; but average daily gain, feed conversion ratio and net feed intake (which are all dependant on weight gain) require a test length of at least 70 days. The combination of data from central tests, where feed intake is measured, with that of on-farm tests where only growth is measured, may be a solution. Another option is to collect body weight more frequently. However, this implies that alternative testing procedures will have to be investigated.